Jake Long, Ryan Clady, Andre Smith or Will Beatty

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The Chargers desperately need help on the offensive line. Their weakest area is tackle. If San Diego can reel in a top tackle, specifically a left tackle, Jared Gaither would immediately be released and forgotten.

Ryan Clady is arguably the best free agent in 2013. He's protected Peyton Manning, an MVP candidate yet again, very well this season and will be the Broncos' first priority this offseason. If he happens to test the market, San Diego should make a run at the 26-year-old.

Jake Long is going to play for a new team in 2013. His days in Miami are over after suffering a triceps injury that put him on IR. The fifth-season veteran will look to protect another quarterback's blindside, unless he's a lefty, next year. Philip Rivers would regain full confidence being protected by Long.

Will Beatty has protected Eli Manning very well in his young career. 2012 has been a breakout season for Beatty, who will look to make big money in the offseason. Although the Giants do not have a list of notable players becoming free agents, they may not offer Beatty the contract he thinks he deserves.

Andre Smith, unlike the other three, is a right tackle. Let's just say this: You can't get much worse than Jeromey Clary. If the Chargers added Smith, they would likely draft a left tackle in the first round.

Andy Levitre

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The Buffalo Bills have two guards becoming free agents in 2013: Kraig Urbik and Andy Levitre.

While they'll have to decide who the better player is, Kraig Urbik is a restricted free agent, so San Diego should have the opportunity to make a run at Levitre. Tyronne Green and Rex Hadnot, the Chargers' two left guards, would most likely not be re-signed if Levitre is brought in.

It would cost a large amount of money, something San Diego doesn't usually do, which makes the addition of a top tackle unlikely.

Either way, the offensive line will most likely be addressed in the NFL draft as well.

Marcus Trufant

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Quentin Jammer is past his prime.

Although he has two touchdowns this season, the only two of his career, he constantly gets beat on double moves by speedy receivers. His inability to keep up has put too much pressure on San Diego's safeties.

Marcus Trufant isn't much younger than Jammer, but he's much better. He'll be searching for a new team in 2013 after Richard Sherman took his starting job in Seattle.

Trufant would be a great addition to a young secondary that needs veterans. It would only work if Trufant agreed to a short-term contract.

Ramses Barden

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Ramses Barden has made the most of his 2012 season due to injuries on the New York Giants. He's 6'6'', making him a perfect target for Philip Rivers.

A trio of Malcom Floyd, Danario Alexander and Ramses Barden would put opposing defenses on their heels. With Philip Rivers, the offense benefits the most with two lengthy receivers. Earlier in the season, the duo of Floyd and Robert Meachem did not work out. Danario Alexander is excelling with Rivers because of his build. It's also opening up the field for the rest of the team as well, especially the tight ends.

Barden should get attention from many teams, but don't expect a Laurent Robinson-type contract.

Luke Joeckel, Taylor Lewan, Jake Matthews or Eric Fisher

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The Chargers will likely take an offensive tackle in the first round of the NFL draft. Luke Joeckel is the top overall prospect as of now, according to CBS Sports. The draft is still months away, so each player's draft stock could rise and fall at any given moment.

One of these four guys should be drafted by San Diego.

In the two mock drafts by Rob Rang and Dane Brugler, the Chargers selected Jake Matthews with the ninth pick of the draft. San Diego's remaining schedule is quite weak, so they could end up 8-8 at the end of the year, which would land them in the middle of the first round. Unless Joeckel falls past No. 10, which is very unlikely, the Chargers will end up drafting Matthews, Lewan or Fisher.

Desmond Trufant

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Senior Desmond Trufant is a 6'0'' cornerback who runs a 4.49 40-yard-dash. Yes, he's the younger brother of Marcus Trufant.

This would be a win-win situation for the Chargers. Desmond would learn from a veteran player who happens to be his brother. He'd listen to someone he looks up to. As of now, Desmond Trufant is projected to go in the second round. San Diego should address its need at cornerback as early as possible.

If all four tackles mentioned in the last slide are taken when the Chargers' first-round selection comes, they could take someone like Johnthan Banks, who was on my list for San Diego last year.

Kenny Stills

The Chargers' experiment with Eddie Royal did not work out. They will be searching for a new slot receiver, one who will make their offense almost unstoppable, like Patrick Crayton did in 2010.

Kenny Stills is a second or third-round prospect the Chargers need. He has above-average speed, as he runs a 4.49 40. With Malcom Floyd, Danario Alexander and Antonio Gates, a slot receiver has a great opportunity to become a star.

San Diego drafted Wes Welker, one of the greatest slot receivers in history. Versatile slots are becoming more and more valuable every year, as Victor Cruz and Randall Cobb have emerged. Kenny Stills could be the next standout in San Diego.